Franz Gysi said:
Thanks Franz, one thing is still not clear to me: in order to reach unity gain or something very close to it should I change some of the board resistors or just short a couple of the opamp's pins?
Unfortunately I still don't have the board in my hands...
Thanks for your patience...
I think it is better to replace the needed resistors, maybe with wire bridges, when needed.
Look for the resistors from inverting input to ground and from output to inverting input.
Regards
Franz
Look for the resistors from inverting input to ground and from output to inverting input.
Regards
Franz
ok, now my head is spinning.
I have zero electronics schooling. Anything I know has been gleaned from here and other informal info gathering done in relation to audio so please bear with me for a second.
From what I understand, a buffer can simply be an opamp with the signal out tied to V-. Is this correct? Has anyone here used a buffer like this and did it sound good? What would some likely candidates be if one was to tap the Vout on the Sure board for voltage? Or is that a bad idea from the start?
I'm not asking for much. I just want the best, cheapest, coolest DIY stereo ever. 😀
I have zero electronics schooling. Anything I know has been gleaned from here and other informal info gathering done in relation to audio so please bear with me for a second.
From what I understand, a buffer can simply be an opamp with the signal out tied to V-. Is this correct? Has anyone here used a buffer like this and did it sound good? What would some likely candidates be if one was to tap the Vout on the Sure board for voltage? Or is that a bad idea from the start?
I'm not asking for much. I just want the best, cheapest, coolest DIY stereo ever. 😀
I've found something, apparently a buffer preamp can be made with just an opamp! Am I missing something? Perhaps I didn't need to buy that board...
Check this out...
http://www.facstaff.bucknell.edu/mastascu/eLessonsHtml/OpAmps/OpAmp3Note1Buffer.html
😕
Check this out...
http://www.facstaff.bucknell.edu/mastascu/eLessonsHtml/OpAmps/OpAmp3Note1Buffer.html
😕
Hi Franz, very nice unusually looking amp, with pot on top. My amp is still "on the desk", I can't settle - I need poweramp without pot, integrated, or tube buffered. Now I am looking to Pedja Rogic buffer too. Wen Arjen's boards arrived, I should try different variants.
pincellone, yes, this is standard unity gain buffer, build it on OPA2134 or better, place right after pot, than good polypropylene input cap (If you remove original SMD) and you have small hi end.
pincellone, yes, this is standard unity gain buffer, build it on OPA2134 or better, place right after pot, than good polypropylene input cap (If you remove original SMD) and you have small hi end.
Thanks, that's good news!
So if I'm not mistaken, in order to get a dual unity gain opamp to be used as a buffer amplifier, I just need to short pin 1-2 and pin 6-7. Also, I should use a unity gain stable one. Is that correct?
An externally hosted image should be here but it was not working when we last tested it.
So if I'm not mistaken, in order to get a dual unity gain opamp to be used as a buffer amplifier, I just need to short pin 1-2 and pin 6-7. Also, I should use a unity gain stable one. Is that correct?
Yes, correct.
And you need 100-500K resistors from positive input (3,5) to ground. Resistor must be x10 pot volume.
And of course you need good =- 12-18V regulated PS.
And you need 100-500K resistors from positive input (3,5) to ground. Resistor must be x10 pot volume.
And of course you need good =- 12-18V regulated PS.
Tripath Boards.
OK Arjen, the board now has between 50 - 70 hours up & running on it. As described, it's fitted with 4700uf tank cap in addition to the 2 x 220uf's allready there, Mundorf M 2.2 Uf input caps, & Alps 50k ohm Blue pot + a To 220 H/S I had lying round. No other changes yet.
Took it inside & wired up, as well as all of the following, to a pair of AR 18 B's
Charlize Mk 2, Sure ( modified ), SI Gen2 ( modified ), Sure (Slightly Modified, C3/C24 & R3 /R16 only).
The above are in the order in which I would describe their performance. The Charlize & modified Sure are quite close, with a noticable gap to the next group of 2 which again are similar. Your board as modified above is close to the slightly modified Sure which to my ears has slightly more top end "sparkle" & a similar bass. At This stage it's pleasant to listen to but I am Sure ( No pun intended ) that it can be improved. All that evaluation was on the AR 18b's.
When using my shack Pioneer 3 way monitors, (1x6" 1x2" & 1x1") the story is diferent with your board, it is a bit brighter up top. ( some of the old AR's can be a bit hard to drive )
Over the weekend I will compare your boards stock & Modified to see exactly where I am at the moment & try & put together a circuit diagram ( That'a a bit slow for me with a bit of an eyesight problem ).
A brief look at the input reveals nothing spectacular resistor wise, where's my cap meter?.. Can't see any low pass filter in the input & will do some component measurements over the weekend also.
Have you made any mod's?? at all & have you looked at the output inductors & associated Cap's ? I see you have removed the inductors off your photo board & assume the filter is 10uH / 0.47uF.
Think I have some 10uF 3amp Panasonic's round here somewhere but dont know what the "Q" is.
Anyone else had a play yet ??
Paul
OK Arjen, the board now has between 50 - 70 hours up & running on it. As described, it's fitted with 4700uf tank cap in addition to the 2 x 220uf's allready there, Mundorf M 2.2 Uf input caps, & Alps 50k ohm Blue pot + a To 220 H/S I had lying round. No other changes yet.
Took it inside & wired up, as well as all of the following, to a pair of AR 18 B's
Charlize Mk 2, Sure ( modified ), SI Gen2 ( modified ), Sure (Slightly Modified, C3/C24 & R3 /R16 only).
The above are in the order in which I would describe their performance. The Charlize & modified Sure are quite close, with a noticable gap to the next group of 2 which again are similar. Your board as modified above is close to the slightly modified Sure which to my ears has slightly more top end "sparkle" & a similar bass. At This stage it's pleasant to listen to but I am Sure ( No pun intended ) that it can be improved. All that evaluation was on the AR 18b's.
When using my shack Pioneer 3 way monitors, (1x6" 1x2" & 1x1") the story is diferent with your board, it is a bit brighter up top. ( some of the old AR's can be a bit hard to drive )
Over the weekend I will compare your boards stock & Modified to see exactly where I am at the moment & try & put together a circuit diagram ( That'a a bit slow for me with a bit of an eyesight problem ).
A brief look at the input reveals nothing spectacular resistor wise, where's my cap meter?.. Can't see any low pass filter in the input & will do some component measurements over the weekend also.
Have you made any mod's?? at all & have you looked at the output inductors & associated Cap's ? I see you have removed the inductors off your photo board & assume the filter is 10uH / 0.47uF.
Think I have some 10uF 3amp Panasonic's round here somewhere but dont know what the "Q" is.
Anyone else had a play yet ??
Paul
Érr.. "Think I have some 10uF 3amp Panasonic's round here somewhere but dont know what the "Q" is."
Obviously should read 10uH....
Paul
Obviously should read 10uH....
Paul
Tripath Boards.
Ok Arjen, it rained today so I got stuck into some more tests. ( it'snowing now )
Wired up a stock board & my modified board for a comparison. Certainly the modified board had better bass, was a bit cleaner with a bit more up top.
OK I expected that.
Then tried ,after reading Franz's posts, bypassing the Pot. I think he may be on to someting as I believe there was a noticable improvement without the Pot, & using the PC to control the volume. Will see what Dual Op Amps are available locally & cobble something up for a trial. Perhaps that's why, to me all T-Amps sound better when driven hard..
All those tests were done at 12.2 Volts on a SMPS as supplied with Sonic Impact Gen 2.
Then repeated above with a 13.6 Volts Linear home brew power supply, 30 amps continuous, with round 130,000uF of Sprague Capacitors on the output.
Drove the modified board hard for 4 hours whilst I did a few chores round the place & got the heatsink definately warm.
What a diference the extra voltage made, it bought out the top end nicely & opened up the whole overall sound.
It's now sounding @ 13.6 Volts, very nice.
Will do some more tests using a SMPS ex an ATM Machine, I can hopefully dial up to over 13 Volts.
Paul
Ok Arjen, it rained today so I got stuck into some more tests. ( it'snowing now )
Wired up a stock board & my modified board for a comparison. Certainly the modified board had better bass, was a bit cleaner with a bit more up top.
OK I expected that.
Then tried ,after reading Franz's posts, bypassing the Pot. I think he may be on to someting as I believe there was a noticable improvement without the Pot, & using the PC to control the volume. Will see what Dual Op Amps are available locally & cobble something up for a trial. Perhaps that's why, to me all T-Amps sound better when driven hard..
All those tests were done at 12.2 Volts on a SMPS as supplied with Sonic Impact Gen 2.
Then repeated above with a 13.6 Volts Linear home brew power supply, 30 amps continuous, with round 130,000uF of Sprague Capacitors on the output.
Drove the modified board hard for 4 hours whilst I did a few chores round the place & got the heatsink definately warm.
What a diference the extra voltage made, it bought out the top end nicely & opened up the whole overall sound.
It's now sounding @ 13.6 Volts, very nice.
Will do some more tests using a SMPS ex an ATM Machine, I can hopefully dial up to over 13 Volts.
Paul
Hi, I'm new at all this 🙂 Do you guys think that this board is good for a beginner? I noticed that it's pretty much all put together and I would need to do some of the mods in this thread. I have a decent head on me 😛 but I haven't worked with these kinds of things since highschool :/
Thanks.
Thanks.
I noticed the price for these boards have gone up again. They are around $30 USD now inc. shipping.
Still a bargain though😉
This is probably the easiest board to modify but even as stock it's got everything except for the case and volume control.... but if you use a PC or iPod then you have digital volume there already.
Maybe Arjen has more boards available? Have a look on the Trade forums, he has a post there... or just PM him......
TTFN
This is probably the easiest board to modify but even as stock it's got everything except for the case and volume control.... but if you use a PC or iPod then you have digital volume there already.
Maybe Arjen has more boards available? Have a look on the Trade forums, he has a post there... or just PM him......
TTFN
PCS's
hi there guys,
Boards are still widly available, i bought 100 PCs so im not run out yet,
i had some shipping issue's, as China post cannot get any electronics thrue customes anymore, dear governement changed the rules on shipping.... like they do every week apparently
but i have found an alternative that is still nicly priced, aldoh its alittle bit more expensive, but just a few Euro.
boards still go for 5 Euro per one, and if people have special requests ill try to take care of it aswell.
Soon ill be having a fully tested TA2022 board too, 100 watts to toy with!
hi there guys,
Boards are still widly available, i bought 100 PCs so im not run out yet,
i had some shipping issue's, as China post cannot get any electronics thrue customes anymore, dear governement changed the rules on shipping.... like they do every week apparently
but i have found an alternative that is still nicly priced, aldoh its alittle bit more expensive, but just a few Euro.
boards still go for 5 Euro per one, and if people have special requests ill try to take care of it aswell.
Soon ill be having a fully tested TA2022 board too, 100 watts to toy with!
Soon ill be having a fully tested TA2022 board too, 100 watts to toy with!
Arjen, that sounds interesting.. Will be able to tune that for maximum smoke..
The Ta-2024's are now sounding really nice on 13.6 volts
Thanks again
Paul
Arjen, that sounds interesting.. Will be able to tune that for maximum smoke..
The Ta-2024's are now sounding really nice on 13.6 volts
Thanks again
Paul
Smokin!
Hi there paul,
Nice! im glad your happy with them! i just made 5 amplifiers with my boards, in beautiful golden color alu housings, alu knobs etc, using a switching powersupply 12 V / 2 A 2uF MKP input caps, 2X 10.000 uF tank caps 3 inputs with with selector switch.
Tried them on my TML's made from stone, i made one pair using HIVI S8II mid woofers and X1 tweeter.
super sound, very happy with them indeed, better than my LM3886 i made before in the mids and highs.
cost me in total about 40 Euro per one, Photo's ill put online tonnight.
Ill post pics of the TA2022 as soon as they arrive!
Greetings from Shenzhen
Hi there paul,
Nice! im glad your happy with them! i just made 5 amplifiers with my boards, in beautiful golden color alu housings, alu knobs etc, using a switching powersupply 12 V / 2 A 2uF MKP input caps, 2X 10.000 uF tank caps 3 inputs with with selector switch.
Tried them on my TML's made from stone, i made one pair using HIVI S8II mid woofers and X1 tweeter.
super sound, very happy with them indeed, better than my LM3886 i made before in the mids and highs.
cost me in total about 40 Euro per one, Photo's ill put online tonnight.
Ill post pics of the TA2022 as soon as they arrive!
Greetings from Shenzhen
Re: PCS's
Really
Now that's going to put the mockers on a lot of business I would have thought!!!!
ArjenShenzhen said:
Really
Now that's going to put the mockers on a lot of business I would have thought!!!!
China post
Yeah, China is making it more and more difficult for anyone to make a buck these days.
this whole olympics thing is costing many people allot of money !
not to mention the thing with getting money in to here and out of here, also not eazy.
Anyway, enough complaining they do have some nice electronics here, hard to find but once your there, lost of stuff!
Yeah, China is making it more and more difficult for anyone to make a buck these days.
this whole olympics thing is costing many people allot of money !
not to mention the thing with getting money in to here and out of here, also not eazy.
Anyway, enough complaining they do have some nice electronics here, hard to find but once your there, lost of stuff!
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